The invention disclosed herein relates to a cassette containing strip, tape or ribbon material (hereafter referred to simply as "ribbon") containing, for example, pigment, wax, resin, ink, etc., particularly for use with printers and plotters. However, the invention is not limited to cassettes containing ribbon for use in printing or plotting.
While the cassette disclosed herein may be used in any suitable printer or plotter, the cassette finds particular application in the thermal strip mode printer described in the cited applications. The cassette disclosed herein may be stored an a turret device, carried by a print carriage during use and moved between the turret storage device and the print carriage as described herein and in the cited applications.
The thermal printer described in the cited applications is capable of thermal transfer printing in wide formats of up to about 36 inches. In doing so, that thermal printer prints in a strip mode of printing where the print or plot is printed one strip at a time in widths (Y-axis direction) of about one inch to about four inches, with strips of about two inches being presently preferred. To print in strips of about two inches in width requires a thermal transfer ribbon of slightly more than two inches in width. In order to provide enough ribbon to print approximately 50 typical color, graphic D size plots, and approximately 100 color typical line art D size plots, width, about 500M of ribbon of each of the four colors in the four color yellow, magenta, cyan and black system are typically required. As a result, reel-to-reel cassettes incorporating that amount of ribbon will have considerable size.
The thermal printer described in the cited applications is a color printer which automatically prints in different colors to provide a composite color print or plot. In order to automatically print in color, the thermal printer incorporates a number of reel-to-reel cassettes each containing ribbon of a different color. In the presently preferred embodiment, the four color system referred to above is used for color printing, which requires four ribbons. Also as presently preferred, the thermal printer includes a primary four color system and a redundant four color system, and therefore incorporates a total of eight reel-to-reel cassettes.
The thermal printer described in the cited applications incorporates an automatic transfer system for transferring ribbons between a storage location and a printing location on a movable print carriage which carries a thermal print head. As described in the cited applications and herein, the transfer system is passive in that the transfer mechanism itself is not servo controlled and operates simply in response to movement of the print carriage towards and away from the cassette storage device, which in the preferred embodiment is a rotatable turret.
Given the relatively large size cassette required to hold 500M of about two inch wide ribbon, and given the stringent requirements for thermal transfer printing described in the cited applications and herein, unwanted movement of ribbon could cause serious problems.
The cassette disclosed herein and in the cited applications was invented in consideration of the factors mentioned in the cited applications and herein, including: size constraints for mounting eight relatively large cassettes in a printer incorporating automatic cassette transfer; configuration constraints on the cassette so as to efficiently mount a number of them on the turret, and one on the print carriage in an efficient print position; preventing unwanted movement of the ribbon in a simple and efficient manner; a simple automatic cassette transfer system; providing for smooth and efficient ribbon delivery to the print head and back to the cassette; protecting the ribbon from contamination and physical damage; possible recycling of the entire cassette or parts thereof; providing an accessible customer interface which protects the customer and reduces difficulties that the customers will have in handling the cassettes; and identifying the cassettes on the turret in a simple manner.
There is therefore a need for ribbon cassettes which satisfy all or various combinations of the factors discussed herein and in the cited applications.